Ocular prosthesis with display device

Abstract

An ocular prosthesis includes a display device visible at an anterior portion of the ocular prosthesis. The display device is configured to present a changeable image that represents a natural appearance and movement for a visible portion of an eyeball of a subject. A system includes, besides the ocular prosthesis, an implant marker configured to move with an orbital implant disposed in an eye socket of a subject. A method includes determining a change in orientation of an orbital implant in a subject and determining an update to a natural appearance for a visible portion of an eyeball for the subject based on the change in orientation of the orbital implant. The method also includes rendering an update to an image of the natural appearance for a display device disposed in an ocular prosthesis configured to be inserted in the subject anterior to the orbital implant.

What is claimed is: 
     
       1. An ocular prosthesis comprising a display device visible at an anterior portion of the ocular prosthesis, wherein the display device is configured to present a changeable image that represents a human appearance for a visible portion of an eyeball of a subject, including position and translation of an image of an iris in a display area on the display device wherein the display device has a pixel density in a range from 50 pixels per inch to 166 pixels per inch, and wherein the ocular prosthesis is configured to fit within a prosthesis space within a closed loop of conjunctiva of the subject. 
     
     
       2. The ocular prosthesis as recited in  claim 1 , further comprising:
 a housing having a form factor shaped to fit under an eyelid of the subject and in front of an orbital implant disposed in an eye socket of the subject, wherein an anterior portion of the form factor is curved similar to an anterior portion of a human eyeball for the subject; 
 wherein the display device is disposed within the housing and visible at an anterior portion of the housing; 
 an implant detector disposed within the housing and configured to detect angular orientation of the orbital implant relative to the subject when the housing is inserted under the eyelid of the subject and anterior to the orbital implant; 
 a processor disposed within the housing and configured to
 determine, at least in part, the human appearance for the visible portion of the eyeball of the subject based, at least in part, on the angular orientation of the orbital implant, and 
 render, at least in part, an image for presentation on the display device as the changeable image based on the human appearance for the visible portion of the eyeball of the subject; and 
 
 a power source disposed within the housing and configured to provide power for the display device, the implant detector and the processor. 
 
     
     
       3. The ocular prosthesis as recited in  claim 2 , further comprising a computer-readable memory disposed within the housing and configured to store data that indicates a color image of an iris for the subject, wherein to determine the human appearance for the visible portion of the eyeball of the subject further comprises to determine the human appearance based, at least in part, on the image of the iris. 
     
     
       4. The ocular prosthesis as recited in  claim 2 , further comprising a light sensor disposed within the housing and configured to detect ambient light level on an anterior portion of the housing, wherein to determine the human appearance for the visible portion of the eyeball of the subject further comprises to determine a size of a pupil based, at least in part, on the ambient light level. 
     
     
       5. The ocular prosthesis as recited in  claim 2 , further comprising a communication module configured to receive configuration data for the processor. 
     
     
       6. The ocular prosthesis as recited in  claim 2 , wherein the power source further comprises an induction coil configured to produce an electric current in response to external electromagnetic radiation. 
     
     
       7. The ocular prosthesis as recited in  claim 6 , wherein the induction coil is further configured as an antenna for a communication module configured to receive configuration data for the processor. 
     
     
       8. The ocular prosthesis as recited in  claim 6 , wherein the power source further comprises a rechargeable battery configured to be charged by the electric current produced in the induction coil. 
     
     
       9. The ocular prosthesis as recited in  claim 2 , wherein the display device is an electronic reflective display device with a display area of 13 millimeters vertically and 25 millimeters horizontally. 
     
     
       10. The ocular prosthesis as recited in  claim 2 , wherein the display device is an electronic reflective display device with a resolution of 81 picture elements per inch and a refresh rate of 18 frames per second. 
     
     
       11. The ocular prosthesis as recited in  claim 2 , wherein the display device is a flexible electronic reflective display device curved in at least a horizontal plane similar to the anterior portion of the housing. 
     
     
       12. The ocular prosthesis as recited in  claim 2 , wherein the display device is shaped as a rectangle with rounded corners. 
     
     
       13. The ocular prosthesis as recited in  claim 2 , wherein the implant detector is further configured to detect an implant marker configured to move with the orbital implant. 
     
     
       14. The ocular prosthesis as recited in  claim 13 , wherein,
 the implant marker is a magnet; and 
 the implant detector is configured to detect a Hall effect when the implant marker moves. 
 
     
     
       15. The ocular prosthesis as recited in  claim 13 , wherein,
 the implant marker is a non-magnetic metal foil, 
 the implant detector further comprises a plurality of non-magnetic metal foils configured to form a variable capacitor; and 
 the implant detector is configured to detect a change in capacitance when the implant marker moves. 
 
     
     
       16. The ocular prosthesis as recited in  claim 13 , wherein,
 the implant marker is a non-magnetic conductor, 
 the implant detector further comprises a plurality of inductance sensors; and 
 the implant detector is configured to detect a change in inductance when the implant marker moves. 
 
     
     
       17. The ocular prosthesis as recited in  claim 13 , wherein,
 the implant marker is a light source, 
 the implant detector further comprises a plurality of light detectors; and 
 the implant detector is configured to determine changes in light intensities detected from the light source in at least three of the plurality of light detectors. 
 
     
     
       18. The ocular prosthesis as recited in  claim 17 , wherein,
 a first light detector of the plurality of light detectors is disposed near a center of a posterior side of the housing, 
 a first subset of the plurality of light detectors different from the first light detector is disposed near an outer edge of the posterior side of the housing; and 
 a second subset of the plurality of light detectors different from the first subset and the first light detector is disposed between the center and the outer edge of the posterior side of the housing. 
 
     
     
       19. The ocular prosthesis as recited in  claim 17 , wherein,
 the implant marker comprises fluorescent material in a vessel configured to be attached to a subject's conjunctiva adjacent to the orbital implant; and 
 the implant detector further comprises a light emitting diode to excite the fluorescent material. 
 
     
     
       20. The ocular prosthesis as recited in  claim 17 , wherein,
 the implant marker is a light emitting diode powered by a receiving antenna disposed inside a vessel configured to be attached to a subject's conjunctiva adjacent to the orbital implant; 
 the ocular prosthesis further comprises a transmitting antenna disposed within the housing; and 
 the implant detector is further configured to power the light emitting diode by sending a time varying current through the transmitting antenna to be received at the receiving antenna. 
 
     
     
       21. The ocular prosthesis as recited in  claim 17 , wherein
 the plurality of light detectors comprises a plurality of photodiodes; and 
 the implant detector further comprises:
 a plurality of dual matched preamps, each pair of dual matched preamps connected to one photodiode of the plurality of photodiodes; 
 a plurality of differential output amplifiers, each differential output amplifier connected to one pair of dual matched preamps of the plurality of dual matched preamps; and 
 a multiplexer connected to the plurality of differential output amplifiers. 
 
 
     
     
       22. The ocular prosthesis as recited in  claim 17 , wherein
 the plurality of light detectors comprises a plurality of photodiodes; and 
 the implant detector further comprises a circuit configured to bias each photodiode at zero bias voltage.